Control valve arrangement for a hydraulic apparatus

ABSTRACT

A hydraulic apparatus receives pressure fluid through a control valve having a valve slide which is rotatable by the hydraulic apparatus, and also axially movable between a closing position stopping the hydraulic apparatus, and an open position supplying fluid to the same so that it rotates. Pressure is exerted in chambers at the ends of the valve slide to hold the same balanced in the closing position. When a pressure differential between the chambers is produced by rotation of control means, the valve slide moves to the open position so that the hydraulic apparatus rotates, and also drives the valve slide in synchronism with the control means so that the valve slide remains in the open position until rotation of the control means is stopped. As a result, the hydraulic apparatus rotates only when the control means rotates.

United States Patent Bartholomiius et al.

[54] CONTROL VALVE ARRANGEMENT FOR A HYDRAULIC APPARATUS [72] Inventors: Relner Bartholomiius, Lohr am Main;

Holger Krohn, Wombach, both of Germany ...,u. 1 /4 ll 51 May 30, 1972 3,310,284 3/1967 Seiuemon Inaba et al ..9l/378 Primary Examiner-Everette A. Powell, Jr. Assistant Examiner-Clemens Schimikowski Attorney-Michael S. Striker [57] ABSTRACT A hydraulic apparatus receives pressure fluid through a control valve having a valve slide which is rotatable by the hydraulic apparatus, and also axially movable between a closing position stopping the hydraulic apparatus, and an open position supplying fluid to the same so that it rotates. Pressure is exerted in chambers at the ends of the valve slide to hold the same balanced in the closing position. When a pressure differential between the chambers is produced by rotation of control means, the valve slide moves to the open position so that the hydraulic apparatus rotates, and also drives the valve slide in synchronism with the control means so that the valve slide remains in the open position until rotation of the control means is stopped. As a result, the hydraulic apparatus rotates only when the control means rotates.

14 Claims, 2 Drawing Figures A V A CONTROL VALVE ARRANGEMENT FOR A HYDRAULIC APPARATUS BACKGROUND OF THE INVENTION Control valve arrangements for hydraulic apparatus such as hydraulic motors are known in which a rotary input control shaft is connected by a thread with a valve slide to shift the same in axial direction for opening the valve so that pressure fluid can flow to the hydraulic apparatus and the same starts to operate and influences a return shaft which causes closing of the valve when the input control shaft is stopped.

Valve arrangements of this type are also known in which the valve slide is rotatable. In the known valve arrangements for controlling the operation of a hydraulic apparatus, substantial flow resistance and friction resistance has to be overcome by the control shaft, and the speed of the operation is reduced by inertia of the parts, and the response is slow.

SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of known control valve arrangements for hydraulic apparatus, and to provide a control valve arrangement requiring low control power, and being highly sensitive and responsive.

Another object of the invention is to provide a control valve arrangement for rotating a hydraulic apparatus only during rotation of a control shaft.

With these objects in view, the present invention provides a valve slide which is subjected to fluid pressure in at least one direction, while the fluid and pressure can be influenced by coupling means between first control means which are rotated as desired, and second control means which are rotated by the hydraulic apparatus when the same operates in the open condition of the valve. Due to the control of the valve slide by pressure fluid, the time required for response is short, and only a low input torque is required for rotating the first control means.

An embodiment of the invention comprises valve body means; valve slide means mounted in the valve body means for rotary movement, and also for translatory movement between aclosed position disconnecting the hydraulic apparatus, and at least one open position in which the hydraulic apparatus is driven by pressure fluid and rotates, the valve slide means forming in the valve body means first and second end chambers; pressure producing means for producing opposing pressures in the end chambers and including conduit means in the valve slide means for supplying pressure fluid to at least one of the end chambers, the other end chamber containing a spring or also pressure fluid; first control means, preferably including an input control shaft, rotatable relative to the valve slide means and conduit means between a normal position for maintaining in one end chamber a normal pressure at which the valve slide means is balanced in the closed position, and an actuating position displaced relative to the conduit means and the valve slide means for producing in the one end chamber a different pressure at which the valve slide means is displaced by the pressure differential between the end chambers from the closed position to the open position so that the hydraulic apparatus rotates; and second control means preferably including a second control shaft connected with the valve slide means, driven from the rotating hydraulic apparatus for rotating the valve slide means with the conduit means in synchronism with the first control means.

As a result, the first control means remains in the actuating position relative to the conduit means until rotation of the first control means is stopped and the second control means rotates with the valve slide means and said conduit means further relative to the first control means. In this manner, the normal relative position between the first control means and the conduit means, and the normal pressure in the one end chamber are again restored. The valve slide means moves to the closed position for disconnecting the hydraulic apparatus and for stopping rotation of the same and of the valve slide means by the second control means so that the hydraulic apparatus rotates only when the first control means is rotated.

In the preferred embodiment of the invention, the valve slide means has a tubular end portion at one end, and a first control means includes a first control shaft having a control portion located in the tubular end portion and having a control edge extending across and cooperating with a port of the conduit means. The second control means include a second control shaft driven from the hydraulic apparatus and secured to the valve slide means for rotating the same.

The tubular end portion has a smaller diameter than the main portion of the valve slide means so that one end chamber is annular and surrounds the tubular end portion.

The control portion of the first control shaft includes ducts for discharging fluid from the conduit means and from the one end chamber whereby a pressure difierential is created between the end chambers, and the valve slide means is longitudinally moved from its balanced closed position to the open position in which pressure fluid is supplied through the valve to the hydraulic apparatus for driving the same.

In one embodiment of the invention, a spring is provided in the other end chamber. In another embodiment of the invention, pressure fluid is supplied to both end chambers, but the same have different effective surfaces, and the first control means either permit pressure fluid to enter both end chambers so that the control slide valve is displaced, or the end chamber having the greater effective surface is connected with a discharge outlet for reducing the pressure in the same.

In the first embodiment of the invention, the first control means include a first control shaft having a slanted end face bounded by a control edge, and ducts are provided leading to a discharge outlet, and opening in the end face of the first control shaft. In the second embodiment of the invention, the control portion of the first control shaft has a helical projection formed with control edges, and having a greater axial width than cooperating ports.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING which end chambers at both ends of the control valve slide are filled with pressure fluid.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1 and 2, a valve body 1 has a cylinder bore in which a valve slide 2 is mounted for rotation and translatory axial movement. An input control shaft 3 has a portion located in the interior of a tubular end portion 6 of valve slide 2. A feed back second control shaft 5 is integral with valve slide 2. The tubular end portion 6 of valve slide 2 is supported for turning and translatory movement with the valve slide in a fluidtight, sealed bushing 7 which is secured against axial movement by a spring ring 8 engaging a groove in valve body 1. An annular end chamber 1 l is formed between the annular shoulder 10 of valve slide 2 and by a portion of the outer surface of the tubular end portion 6, in the valve body means 1 and 7. The annular end chamber 1 l is connected by a radial bore 14, a longitu- The longitudinal bore 13 is extended at 13a and closed by a screw at the end of the tubular end portions 6. A transverse bore 17 intersects conduit 13a and has a port opening at the inner surface of tubular end portion 6 in the space 33 which is closed by the slanted end face of the control shaft 3. The control portion of control shaft 3 which is located in the interior of the projecting end portion 7, has discharge ducts 34, 35 connecting the space 33 with an annular chamber 36 which communicates through radial discharge ducts 37 with discharge outlet means 39. The annular peripheral control edge 18a of the end face of control shaft 3, cooperates with a port formed by the radial bore 17.

The flange 19 of control shaft 3 abuts inner rings 20a and 21a of ball bearings 20 and 21. The outer ring 20b of ball bearing 20 abuts a threaded ring 22, while the outer ring 21b of ball bearing 21 abuts the spring ring 23 so that neither the control shaft 3, nor bushing 7 are movable in axial direction in valve body 1. A sealing means 24 seals the interior of the valve body.

A cover 25 provided with sealing means 29 closes the other end of the cylinder bore of the valve body 1, and is fixed against axial movement by spring ring 26. The control shaft passes through the sealing means 29 and is integral with valve slide 2. Cover 25 forms with a reduced portion of valve slide 2, another end chamber 32 in which a spring 28 is located, abutting at one end on cover 25 and at the other end on a ball bearing 27 so that valve slide 2 can rotate while under pressure by spring 28.

A conduit 31 connects the space 33 with a transverse conduit 30 which opens into the end chamber 32. The valve body 1 is provided with an outlet 40 which discharges into a container from which a pump, not shown, sucks pressure fluid and pumps the same into the pressure inlet 15, as indicated by the arrows T and P. Outlet 40 communicates with an annular recess 41 in valve slide 2 which has a control edge 48a. lnlet communicates with the annular recess 16 which has a control edge 48b, and a control edge 49a. An annular recess 46 in valve body 1 is disposed between control edges 48a and 48b in the illustrated closed position of the valve. Another annular recess 47 in valve body 1 is located between control edge 49a, and control edge 49b of an annular recess 43 in valve slide 2. A bore 42 in valve body 1 is connected with outlet 40, and with the annular recess 43 in valve slide 2. Connectors 44 and 45 respectively communicate with the annular recesses 46 and 47 in the valve body 1. Connectors 44 and 45 are connected with the outlet and inlet of a hydraulic apparatus 100 which rotates when fluid is supplied to the same, and drives through a transmission 101, 5a, the end portion 5a of the second control shaft 5 as long as the hydraulic apparatus operates.

The control valve arrangement illustrated in FIG. 1 operates as follows.

When the input control shaft 3 is at a standstill, the pressure of spring 28 is opposed by the fluid pressure in end chamber 11 which receives pressure fluid from inlet 15 through recess 16, throttle 12a, conduit 13, and conduit 14. When the valve is in a balanced position in which the annular recesses 46 and 47 are closed by control edges 48a, 48b, 49a, 49b, the annular control edge 18a of the inner portion of input control shaft 3 opens the port of conduit 17 just so far that the amount of pressure fluid flowing out of end chamber 1 1 reduces the pressure in the same sufficiently that the force of spring 28 is just balanced. The pressure fluid flowing into space 33 is discharged through discharge ducts 34, 35, chamber 36, ducts 37 and discharge outlet 39. As a result, when input control shaft 3 is at a standstill, the control valve is in the illustrated closed position, and the hydraulic apparatus is not driven since no fluid is supplied or returned through connectors 44, 45.

When input control shaft 3 is rotated, for example by an electric impulse motor operating in accordance with a program, the open portion of the port of conduit 17 is varied by displacement of the control edge 18a so that the equilibrium between the forces acting in the end chambers 11 and 32 is disturbed, and valve slide 2 moves in axial direction.

When the displacement of valve slide 2 in a turned actuated position of control shaft 3 increases the open portion of the port more fluid is discharged from end chamber 11, and the force of spring 28 prevails to move valve slide 2 to the left as viewed in FIG. 1 so that control edges 48b, 49b establish a connection between annular recess 46 and annular pressure chamber 16, and also a connection between annular recess 47 and the annular recess 43 which communicates through conduit 42 with a dischargeoutlet 40 to the container. Since the hydraulic apparatus is thus provided with pressure fluid through connector 44, and can discharge through connector 45, it starts to rotate, and its rotor drives through a transmission member 101, the fluted end portion 5a of the second control shaft 5 which turns control valve 2 in valve body 1.

The arrangement is such that the second control shaft 5 is rotated in the same direction of rotation, and in synchronism with the rotation of the input control shaft 3. Consequently, the degree of opening of the port of conduit 17 by control edge 18 is maintained since there is no relative angular displacement between the input control shaft 3, and the feed back control shaft 5 with control valve 2 and its conduits.

When input shaft 3 is stopped in accordance with the program controlling the operation of the hydraulic apparatus indicated by the arrows A and B, the hydraulic motor or apparatus 100 can only turn a small angle with second control shaft 5 and slide valve 2 relative to control edge 18a of the stopped input shaft 3 until the normal position of control edge 18a on the port of conduit 17 is again obtained. Due to axial displacement of valve slide 2, the connectors 44 and 45 are again closed so that the hydraulic apparatus stops.

When input control shaft 3 is turned in the opposite direction, and the open portion of the port of conduit 17 formed by the control edge 18a is reduced, the pressure in end chamber 11 increases, and valve slide 2 is moved in axial direction against the action of spring 28 so that the control edges 48a, 49a establish a connection with the annular recesses 46 and 47 whereby the input line B is connected with the pressure source P, and the return line A is connected with the container T so that the hydraulic apparatus rotates in the opposite direction, as explained above, together with the feed back control shaft 5 and valve slide 2 so that the port of conduit 17 and the control edge 18a rotate in synchronism and the opening of the port is not changed during rotation of input shaft 3.

When input shaft 3 is stopped, the hydraulic apparatus and shaft 5 turn an angle corresponding to the width of the open portion between control edge 18a and the port of conduit 17 until the equilibrium between the pressure and spring forces acting on valve slide 2 is again obtained and valve slide 2 assumes the closed position shown in FIG. 1.

In the embodiment of FIG. 2, parts corresponding to parts of FIG. 1 are indicated by like reference numerals.

The valve arrangement has an end chamber 1 1, as described with reference to FIG. 1, and another end chamber 62. Both end chambers are annular, but end chamber 62 has a greater effective annular surface 61 than the annular surface 10 of end chamber 11 so that, when the same pressure is present in end chambers 11 and 62, the pressure of end chamber 62 prevails and valve slide 2 moves to the left. No spring is provided in end chamber 62.

Control shaft 3 has a shaft portion formed with a helical ridge 53 between which recesses are formed. The helical ridge has a control edge 18b, cooperating with the port of conduit 17, and a control edge 18c cooperating with a second port formed by conduit 50 communicating with conduit 51 which opens into the annular discharge chamber 36 which communicates through discharge duct 47 and recess 48 with the discharge outlet 39. The helical recess 54 communicates with the annular recess 48 in the region 57 of the portion of input shaft 3 which is located in cylindrical bore of the tubular end portion 6 in which shaft portion 57 forms a space 33. The axial extension of the helical ridge 53 is sufficient to completely cover the ports of ducts 17 and 50. A duct 59 opens into annular recess 58 and communicates with a conduit 60 opening into the end chamber 62. The effective surface of end chamber 62 is advantageously twice the effective surface of end chamber 1 1.

The embodiment illustrated in FIG. 2 operates as follows.

When the input shaft 3 is driven by an electric motor in accordance with the program to rotate and stop in a certain timed sequence, the control edge 18b opens the port of conduit 17 during rotation in one direction, while the control edge 18c moves to a position closing the port of discharge conduit 50. Since the port of conduit 17 is opened, fluid flows through the helical recess 54, the annular recess 58, and conduits 59, 60 into the end chamber 62 at the same pressure as prevails in end chamber 11, so that valve slide 2 moves to the left as viewed in the drawing due to the fact that at equal pressure, the greater effective surface of end chamber 62 produces a pressure differential between chambers 11 and 62. The discharge line A is connected by connector 44, and annular recess 46 with pressure chamber 16 and with the pressure inlet 15, while the line B is connected by the gap between the control edge 49b and the annular recess 47 with recess 43, conduit 42 and discharge outlet 40.

Due to the supply of pressure fluid from the source P to the hydraulic apparatus, not shown in FIG. 2 through connector 44, and a discharge of the fluid through connector 45, the hydraulic apparatus rotates and drives the feed back control shaft 5 in synchronism with input control shaft 3 and in the same direction of rotation. Since the ports rotate at the same speed as the control edges, the relative position between the same is not changed, and the valve slide 2 remains in the open position while the open flow cross sections of the ports remain the same.

When input shaft 3 is stopped, the hydraulic motor and the control shaft 5 driven from the same continue to rotate a small angle. In order to equalize the pressures acting in chambers l l and 62 on valve slide 2, the port of conduit 17 must be covered by the control edge 18b so that the communication between the end chambers 11 and 62 is interrupted, while at the same time, the port of discharge conduit 50 is opened by control edge 18c so that pressure fluid can be discharged from end chamber 62 through conduit 60, conduit 59, annular chamber 58, helical recess 54, conduits 50 and 51, annular space 36, ducts 37, recess 38 and discharge outlet 39. The port of conduit 50 is opened by control edge 180 just wide enough that the amount of pressure fluid escaping from end chamber 62 reduces the pressure in the same to such an extent that the forces exerted by the fluid in end chambers 1 l and 62 balance each other and valve slide 2 is balanced in the closed position shown in FIG. 2. When this position is reached, the port of conduit 50 is closed by the control edge 18c.

The connection between the fluid pressure chamber 16 and the connectors 44 and 45 is interrupted, so that hydraulic apparatus stops with control shaft 5.

When the direction of rotation of input shaft 3 is reversed, control edge 18c opens the port of conduit 50 which communicates with the discharge outlet 39, while control edge 18b closes the port of conduit 17 leading to end chamber 1 1.

When the port of conduit 50 is opened, the pressure in end chamber 62 is reduced so that the pressure in end chamber 11 moves valve slide 2 to the right as viewed in the drawing so that the control edges 48a, 49a open the recesses 46, 47. Since in this manner, the line B is connected with the pressure source P, and the line A is connected with the container T, the hydraulic apparatus rotates together with control shaft 5 in the same direction as input shaft 3.

- When input shaft 3 is again stopped, the hydraulic ap paratus and shaft 5 continue to rotate a small angle until the pressure forces in the end chambers 11 and 62 on opposite sides of valve slide 2 are equalized. The port of conduit 50 has to be closed, and the port of conduit 17 has to be opened to increase the pressure in end chamber 62 which corresponds to the force acting in end chamber 11 on valve slide 2.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of control valve arrangements for hydraulic apparatus, particularly hydraulic motors, differing from the types described above.

While the invention has been illustrated and described as embodied in a control valve arrangement in which a valve slide is controlled by a rotary input shaft and by a rotary feed back shaft driven from a hydraulic motor receiving pressure fluid from the valve arrangement, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. Control valve arrangement for a hydraulic apparatus, comprising valve body means having a cylinder bore; valve slide means mounted in said bore of said valve body means for rotary movement, and also for translatory movement between a closed position disconnecting the hydraulic apparatus, and at least one open position in which said hydraulic apparatus is driven by pressure fluid, said valve slide means forming conduits; first input control means mounted in said valve slide means for rotation relative to said conduits, and having a nor mal position cooperating with said conduits for maintaining said valve slide means balanced in closed position, and an actuating position displaced relative to said conduits for producing a pressure differential for displacing said valve slide means from said closed position to said open position so that said hydraulic apparatus is driven; and second feedback control means driven from said hydraulic apparatus for rotating said valve slide means with said conduits in synchronism with said first input control means so that said first control input means remains in said actuating position relative to said conduits of said valve slide means until rotation of said first input control means is stopped and said second feed back control means rotates said valve slide means further relative to said first input control means so as to restore said normal position of said first input control means and said closed balanced position of said valve slide means whereby said hydraulic apparatus is disconnected so that said second feed back control means stops with said valve slide means whereby said hydraulic apparatus moves only while said first control means is rotated.

2. The control valve arrangement of claim 1 wherein said valve slide means forms a pair of end chambers in said valve body means, at least one of which communicates with said conduits; wherein said conduit means have at least one control port in said valve slide means; wherein said first control means includes at least one control edge cooperating with said control port, and discharge duct means; and wherein said control edge closes said port in said normal position when the pressure forces exerted on said valve slide means in said end chambers are equal and said valve slide means is in said balanced position, and opens said port in said actuating position for connecting said conduit means and one of said end chambers with said discharge duct means for producing said pressure differential between said end chambers.

3. The control valve arrangement of claim 1 wherein said slide valve means forms end chambers in said valve body means at the ends thereof; comprising pressure producing means for producing opposing pressures in said end chambers and connected with said conduit means for supplying pressure fluid to at least one of said end chambers; wherein said first control means maintain in said normal position in said one end chamber a normal pressure at whhich said valve slide means is balanced in said closed position, and produce said pressure differential between said end chambers in said actuating position.

4. The control valve arrangement of claim 3 wherein said valve slide means has a tubular end portion at one end; wherein said first control means includes a first control shaft having a control portion located in said tubular end portion for relative rotation; wherein said second control means include a second control shaft driven from said hydraulic apparatus for rotating said valve slide means; and wherein said conduit means include a port in said tubular end portion cooperating with said control portion of said first control shaft to vary the flow to and from said one end chamber.

5. The control valve arrangement of claim 4 wherein said tubular end portion has a smaller diameter than the main portion of said valve slide means so that said main portion has an annular shoulder around said projecting tubular end portion; wherein said tubular portion and said annular shoulder form said one end chamber with said valve body means; and wherein said conduit means connects said one end chamber through said port with the interior of said tubular end portion.

6. The control valve arrangement of claim 5 wherein said main portion of said valve slide means and said valve body means form an annular pressure chamber; wherein said valve body means has a pressure fluid inlet means communicating with said annular pressure chamber; wherein said conduits connect said annular pressure chamber with said one end chamber; and wherein said control portion of said first control shaft includes means for discharging fluid from said conduits and from said one end chamber.

7. The control valve of claim 6 wherein said conduits include a longitudinal bore in said valve slide means, and three transverse bores connecting said longitudinal bore with said annular pressure chamber, said one end chamber, and with said port, respectively, said longitudinal bore being partly located in said tubular end portion and in said main portion.

8. The control valve of claim 6 wherein said valve slide means includes throttling means disposed in said conduit means between said annular pressure chamber and said one end chamber; and wherein said pressure producing means comprise a spring in the other end chamber acting on said valve slide means in the direction opposite to the pressure fluid in said one end chamber.

9. The control valve arrangement of claim 8 wherein said control portion of said first control shaft has a slanted control face with a control edge extending across said port in said normal position of said first control means; wherein said means for discharging fluid includes discharge duct means in said control portion opening on said control face, and a discharge outlet means comprised by said valve body means and communicating with said discharge duct means; and wherein said slanted control face forms a space in the interior of said tubular end portion communicating with said duct means and receiving fluid from said one end chamber through said port when the same is opened by said control edge of said control shaft portion.

10. The control valve arrangement of claim 9 wherein said duct means include an axial bore in said control portion opening at said slanted control face, and a transverse bore diametrically extending through said first control shaft crossing said axial bore; and wherein said tubular end portion, said first control shaft, and said valve body means form an annular chamber surrounding said first control shaft and communicating with said transverse bore of said duct means and with said discharge outlet means so that fluid can be discharged from said one end chamber during rotation of said first control shaft.

1 l. The control valve arrangement of claim 10 wherein said valve slide means has connecting duct means communicating at one end with said space and duct means, and at the other end with said other end chamber.

12. The control valve arrangement of claim 1 wherein said slide valve means forms end chambers in said valve body means at the ends thereof, one of said end chambers havin a smaller effective surface than the other; a pressure fluid in ct comprised by said valve body means; wherein said conduits include a first conduit connecting said one end chamber with said pressure fiuid inlet and having a first port, and a second conduit connected with said other end chamber; wherein said valve body means comprise a discharge outlet; wherein said first control means has discharge duct means communicating with said discharge outlet means and having a second port; wherein said first control means include first and second ports, respectively; wherein in said normal position of said first control means, said second control edge and second port connect said second conduit and said other end chamber with said discharge duct means while said first control edge closes said first port so that said valve slide means assumes said balanced closed position since the pressure in said other end chamber which has the greater effective surface is reduced by leakage to said discharge outlet means; and wherein when said first control means is turned to said actuated position, said second control edge opens said first port so that pressure fluid flows from said one end chamber through said second conduit to said other end chamber whereby greater pressure is exerted on said valve slide means in said other end chamber than in said one end chamber and said valve slide means moves to said open position.

13. The control valve arrangement of claim 12 wherein said valve slide means has a tubular end portion; wherein said first control means includes a first control shaft having a control portion having said first and second control edges, and forming recesses between the same, said control portion being located in said tubular end portion of said valve slide means, and said first and second ports being formed in the inner surface of said tubular end portion; and wherein said second conduit opens in the interior of said tubular end portion into said recesses.

14. The control valve arrangement of claim 13 wherein said control portion has a helical ridge having said first and second control edges; wherein said recesses include a helical recess formed by said ridge, and an annular recess in said control portion communicating with said helical recess; and wherein said second conduit includes said helical and annular recesses and a duct connecting said annular recess with said other end chamber; and wherein during rotation of said first control shaft in one direction one of said first and second ports is opened, and during rotation in the opposite direction, the other port of said first and second ports is opened. 

1. Control valve arrangement for a hydraulic apparatus, comprising valve body means having A cylinder bore; valve slide means mounted in said bore of said valve body means for rotary movement, and also for translatory movement between a closed position disconnecting the hydraulic apparatus, and at least one open position in which said hydraulic apparatus is driven by pressure fluid, said valve slide means forming conduits; first input control means mounted in said valve slide means for rotation relative to said conduits, and having a normal position cooperating with said conduits for maintaining said valve slide means balanced in closed position, and an actuating position displaced relative to said conduits for producing a pressure differential for displacing said valve slide means from said closed position to said open position so that said hydraulic apparatus is driven; and second feedback control means driven from said hydraulic apparatus for rotating said valve slide means with said conduits in synchronism with said first input control means so that said first control input means remains in said actuating position relative to said conduits of said valve slide means until rotation of said first input control means is stopped and said second feed back control means rotates said valve slide means further relative to said first input control means so as to restore said normal position of said first input control means and said closed balanced position of said valve slide means whereby said hydraulic apparatus is disconnected so that said second feed back control means stops with said valve slide means whereby said hydraulic apparatus moves only while said first control means is rotated.
 2. The control valve arrangement of claim 1 wherein said valve slide means forms a pair of end chambers in said valve body means, at least one of which communicates with said conduits; wherein said conduit means have at least one control port in said valve slide means; wherein said first control means includes at least one control edge cooperating with said control port, and discharge duct means; and wherein said control edge closes said port in said normal position when the pressure forces exerted on said valve slide means in said end chambers are equal and said valve slide means is in said balanced position, and opens said port in said actuating position for connecting said conduit means and one of said end chambers with said discharge duct means for producing said pressure differential between said end chambers.
 3. The control valve arrangement of claim 1 wherein said slide valve means forms end chambers in said valve body means at the ends thereof; comprising pressure producing means for producing opposing pressures in said end chambers and connected with said conduit means for supplying pressure fluid to at least one of said end chambers; wherein said first control means maintain in said normal position in said one end chamber a normal pressure at whhich said valve slide means is balanced in said closed position, and produce said pressure differential between said end chambers in said actuating position.
 4. The control valve arrangement of claim 3 wherein said valve slide means has a tubular end portion at one end; wherein said first control means includes a first control shaft having a control portion located in said tubular end portion for relative rotation; wherein said second control means include a second control shaft driven from said hydraulic apparatus for rotating said valve slide means; and wherein said conduit means include a port in said tubular end portion cooperating with said control portion of said first control shaft to vary the flow to and from said one end chamber.
 5. The control valve arrangement of claim 4 wherein said tubular end portion has a smaller diameter than the main portion of said valve slide means so that said main portion has an annular shoulder around said projecting tubular end portion; wherein said tubular portion and said annular shoulder form said one end chamber with said valve body means; and wherein said conduit means connects said one end chamber through said port with the interior of said tubular end portion.
 6. The control valve arrangement of claim 5 wherein said main portion of said valve slide means and said valve body means form an annular pressure chamber; wherein said valve body means has a pressure fluid inlet means communicating with said annular pressure chamber; wherein said conduits connect said annular pressure chamber with said one end chamber; and wherein said control portion of said first control shaft includes means for discharging fluid from said conduits and from said one end chamber.
 7. The control valve of claim 6 wherein said conduits include a longitudinal bore in said valve slide means, and three transverse bores connecting said longitudinal bore with said annular pressure chamber, said one end chamber, and with said port, respectively, said longitudinal bore being partly located in said tubular end portion and in said main portion.
 8. The control valve of claim 6 wherein said valve slide means includes throttling means disposed in said conduit means between said annular pressure chamber and said one end chamber; and wherein said pressure producing means comprise a spring in the other end chamber acting on said valve slide means in the direction opposite to the pressure fluid in said one end chamber.
 9. The control valve arrangement of claim 8 wherein said control portion of said first control shaft has a slanted control face with a control edge extending across said port in said normal position of said first control means; wherein said means for discharging fluid includes discharge duct means in said control portion opening on said control face, and a discharge outlet means comprised by said valve body means and communicating with said discharge duct means; and wherein said slanted control face forms a space in the interior of said tubular end portion communicating with said duct means and receiving fluid from said one end chamber through said port when the same is opened by said control edge of said control shaft portion.
 10. The control valve arrangement of claim 9 wherein said duct means include an axial bore in said control portion opening at said slanted control face, and a transverse bore diametrically extending through said first control shaft crossing said axial bore; and wherein said tubular end portion, said first control shaft, and said valve body means form an annular chamber surrounding said first control shaft and communicating with said transverse bore of said duct means and with said discharge outlet means so that fluid can be discharged from said one end chamber during rotation of said first control shaft.
 11. The control valve arrangement of claim 10 wherein said valve slide means has connecting duct means communicating at one end with said space and duct means, and at the other end with said other end chamber.
 12. The control valve arrangement of claim 1 wherein said slide valve means forms end chambers in said valve body means at the ends thereof, one of said end chambers having a smaller effective surface than the other; a pressure fluid inlet comprised by said valve body means; wherein said conduits include a first conduit connecting said one end chamber with said pressure fluid inlet and having a first port, and a second conduit connected with said other end chamber; wherein said valve body means comprise a discharge outlet; wherein said first control means has discharge duct means communicating with said discharge outlet means and having a second port; wherein said first control means include first and second ports, respectively; wherein in said normal position of said first control means, said second control edge and second port connect said second conduit and said other end chamber with said discharge duct means while said first control edge closes said first port so that said valve slide means assumes said balanced closed position since the pressure in said other end chamber which has the greater effective Surface is reduced by leakage to said discharge outlet means; and wherein when said first control means is turned to said actuated position, said second control edge opens said first port so that pressure fluid flows from said one end chamber through said second conduit to said other end chamber whereby greater pressure is exerted on said valve slide means in said other end chamber than in said one end chamber and said valve slide means moves to said open position.
 13. The control valve arrangement of claim 12 wherein said valve slide means has a tubular end portion; wherein said first control means includes a first control shaft having a control portion having said first and second control edges, and forming recesses between the same, said control portion being located in said tubular end portion of said valve slide means, and said first and second ports being formed in the inner surface of said tubular end portion; and wherein said second conduit opens in the interior of said tubular end portion into said recesses.
 14. The control valve arrangement of claim 13 wherein said control portion has a helical ridge having said first and second control edges; wherein said recesses include a helical recess formed by said ridge, and an annular recess in said control portion communicating with said helical recess; and wherein said second conduit includes said helical and annular recesses and a duct connecting said annular recess with said other end chamber; and wherein during rotation of said first control shaft in one direction one of said first and second ports is opened, and during rotation in the opposite direction, the other port of said first and second ports is opened. 